As it enters the final stretch of a massive expansion, the Panama Canal Authority is setting its sights on an even more ambitious project worth up to $17 billion that would allow it to handle the world’s biggest ships.

Workers are now installing giant, 22-story lock gates to accommodate larger “Post-Panamax” ships through the Canal, one of the world’s busiest maritime routes.

The project involves building a third set of locks on the Canal. It is being headed by Italy’s Salini Impregilo and Spain’s Sacyr, and should open on April 1, 2016.